Many integrated circuits utilize passive structures to store energy therein. These passive structures may be used within special-function circuits that provide backup power, boosted on-chip voltages and charge storage, for example. Conventional passive structures include metal-insulator-metal (MIM) capacitors having planar and U-shaped electrodes as well as vertical capacitors that utilize interconnect and trench-based electrodes located side-by-side within interlayer insulating layers. One such capacitor network that includes a MIM capacitor with patterned upper and lower electrodes and capacitively coupled electrode interconnects is disclosed in US 2007/0228506 to Min et al.
Unfortunately, techniques to increase the capacitance of integrated circuit capacitors typically involve relatively complicated fabrication processes and/or require relatively large area capacitor electrodes that reduce the overall integration density of circuits within a semiconductor substrate. To address these limitations associated with conventional capacitor fabrication techniques, new capacitor dielectric materials have been developed with increased dielectric strength. However, the use of these alternative materials can complicate fabrication processes and result in unwanted increases in parasitic coupling capacitances when used in proximity to non-capacitor structures and active devices. Thus, there continues to be a need for improved techniques for fabricating integrated circuit capacitors having relatively high capacitance and relatively high integration densities, that do not significantly increase fabrication complexity.